Fig. 4From: Prevalence, characteristics, and costs of diagnosed homocystinuria, elevated homocysteine, and phenylketonuria in the United States: a retrospective claims-based comparisonProportion of costs attributable to different healthcare services. ER: emergency room; HCU: homocystinuria; OP: outpatient; PKU: phenylketonuria; tHcy: total homocysteineBack to article page